The present disclosure relates to a wind power generation unit, a wind farm which improves the degree of agglomeration, and arrangement structure and control method of the same, and more particularly, to a wind power generation unit, a wind farm, and arrangement structure and control method of the same, which facilitate arrangement of more wind power generation units in the same area by minimizing vortex interaction between the wind power generation units.
In wind power generation, a power generation facility converts kinetic energy of wind into rotational energy of blades and produces electricity by operating an electric generator inside a nacelle.
Referring to FIG. 1, a wind farm includes a plurality of wind power generation units whose blades rotate in the clockwise direction and are arranged at sufficient longitudinal intervals and transversal intervals from each other in order to avoid a mutual interference. Therefore, an initial task in creating a wind farm including dozens or hundreds of wind power generation units is to secure enough land to arrange the wind power generation units at sufficient distances from each other.
It can be considered to narrow the distance between the wind power generation units in order to increase power capacity per land unit, but it may cause a vibration of the blades due to vortex interaction generated by rotation of the blades of each wind power generation unit. Because the lifespan of the wind power generator is reduced due to such a vibration, in reality, there is a limitation in narrowing the distance between the wind power generation units.
In more detail, between the wind power generation units neighboring in a longitudinal (back and forth) direction as shown in FIG. 2, a rear vortex moves in the opposite direction to the rotational direction of the blades while wind passing the blades collides with the blades. That is, in the case of A1 of FIG. 2, while the blades rotate in the clockwise direction, a rear vortex is generated in the counterclockwise direction and is transferred to B1.
FIG. 3 illustrates an influence of the rear vortex more concretely. As shown in FIG. 3, the wind power generation units of A1, B1 and C1 are all arranged in the longitudinal (back and forth) direction and all rotate in the clockwise direction. In this instance, all of the wind power generation units generate the rear vortex in the counterclockwise direction, and the rear vortex are overlapped and gradually amplified from A1 toward B1 and C1. As described above, in the conventional wind farm, the wind power generation units are arranged in the longitudinal (back and forth) direction at a sufficient distance from each other to avoid such an influence of the rear vortex in the longitudinal (back and forth) direction.
Meanwhile, between wind power generation units which are adjacent to one another in a transversal (lateral) direction, a vortex which rotates in the opposite direction to a rotational direction of the blades is generated when wind passing the blades collides against the blades. That is, in FIG. 5, a vortex directing downward is generated at the right side of A1 but a vortex directing upward is generated at the left side of A2. Therefore, mutual collision of the vortexes causes a vibration of the blades.
In more detail, conventionally, in case that a plurality of wind power generation units are installed, a longitudinal (back and forth) interval which is about seven times the rotor diameter must be maintained in order to prevent an efficiency drop and a vibration of the wind power generation units installed at the rear due to a slipstream flow generated by the wind power generation units installed at the front, and a transversal (lateral) interval which is about four times the rotor diameter must be maintained in order to prevent an efficiency drop and a vibration of wind power generation units due to a vortex interaction generated by the wind power generation units installed laterally, and hence, there is a limitation in increasing the degree of agglomeration of the wind power generation units.